I have a 15-20 year old oleander that is planted in the corner of our very large backyard. In the past we have only cut it down when it got to big and unruly. It keeps growing new stems from the base of the plant. We keep cutting them but new ones grow back. Some of these are growing from the roots. How do we keep more from growing and kill the ones that are two small. It has about 10-12 large size trunks that we would like to keep growing. No matter how far back we have cut this down in the past it comes back.
Thanks

Its being an oleander. There's no stopping them. The best way to discourage shoots off the roots is pull them off, not cut them off. You can keep it to just a few trunks but you will always have the cut off branches packed around the base.

Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and proclaiming...."WOW What a Ride!!" -Mark Frost